Astragalus spatulatus

Title

Astragalus spatulatus

Authors

Rupert C. Barneby

Scientific Name

Astragalus spatulatus E.Sheld.

Description

67. Astragalus spatulatus

Low, dwarf, or diminutive, tufted, matted, or pulvinate, the repeatedly forking caudex beset with a thatch of persistent stipules and leaf-bases, the herbage densely strigulose with fine, straight, appressed, or some looser and sinuous, but commonly parallel and contiguous hairs up to 0.5-0.9 (1) mm. long, silvery or cinereous; stems mostly reduced to crowns, the year’s growth not exceeding 1.5 cm. in length, the intemodes all concealed by imbricated stipules, together forming small tufts, prostrate mats, or domed cushions up to 3 dm. in diameter, mostly smaller; stipules papery-scarious, 2-7 mm. long, those of the short outer phyllodia the smallest, all amplexicaul and connate through at least half their length into a bidentate or subentire sheath, either all glabrous dorsally, all strigulose, or the outer ones only pubescent, the margins bristly-ciliate, at least distally; leaves all or mostly reduced to phyllodia, ± dimorphic, the lower ones spreading or decurved, 0.3-1.5 cm. long, oblanceolate or narrowly spatulate, nearly always expanded upward into a definite blade as long or longer than the petiole-like base, the later ones similar but more erect, always longer and commonly narrower, (1) 1.56 cm. long, oblanceolate or linear-oblanceolate, acute, mucronulate, or subacute, mostly simple, but a few sometimes bearing 1 (2) pairs of lateral leaflets similar in shape, the blades either fiat, or with elevated or involute margins; peduncles erect or ascending at anthesis, the outer ones of a plant often prostrate in fruit, 0.4—7 cm. long, in the most condensed states barely surpassing the stipules, but in the looser ones sometimes surpassing the longest leaf; racemes shortly but loosely, more rarely subcapitately (1) 2—9 (ll)-flowered, the axis 1—35 mm. long in fruit; bracts scarious, ovate, lanceolate, or lance-attenuate, somewhat involute, 0.5—4 (6) mm. long; pedicels ascending, straight or nearly so, at anthesis 0.3—1.7 mm., in fruit 0.7-3 mm. long, persistent until or after the fruit is ripe; bracteoles 0, rarely present and up to 3 mm. long; calyx (2.6) 3.5-5 mm. long, densely strigulose with white, partly black, or wholly black hairs, the symmetric disc (0.3) 0.4—0.6 mm. deep, the campanulate or obconic-campanulate tube 1.9—3 (3.4) mm. long, 1.5— 2.1 mm. in diameter, the erect, subulate, sometimes incurved teeth 0.5—2.3 (2.5) mm. long; petals bright pink-purple with white wing-tips, rarely cream-colored, veined and suffused with dull lilac, exceptionally white; banner recurved through ± 45°, sometimes further, (5.7) 6.5—9.5 mm. long, variable in outline, the cuneate claw expanded into an ovate, obovate, or less often rhombic-elliptic or sub- orbicular, notched blade (4.1) 4.5—6.7 mm. wide; wings (5.1) 6—8.3 mm. long, the claws (1.7) 2-3.2 mm., the lunately oblong-elliptic or -oblanceolate, obtuse blades (3.6) 4-5.8 mm. long, (1.3) 1.6-2.3 mm. wide, both incurved but the left one more strongly so and its inner margin infolded; keel (4) 4.5-6.2 mm. long, the claws (1.5) 1.9-3.2 mm., the obliquely obovate or half-circular blades 2.2-3.3 mm. long, 1.5-2.1 mm. wide, abruptly incurved through 100-135° to the rounded, rarely subporrect apex; anthers (0.25) 0.3—0.5 mm. long; pod erect or ascending at a narow angle, sessile, commonly disjointing before dehiscence but sometimes subpersistent, narrowly lanceolate, lance-oblong, or ovate in profile, (4) 5-13 mm. long, 1.5-3 (3.3) mm. in diameter, straight or a trifle incurved, rounded at base, abruptly acute or shortly acuminate at apex, cuspidate, laterally compressed and 2-sided, bicarinate by the salient sutures but more sharply so ventrally, the faces low-convex (more turgid toward the dorsal suture), the pale green, purple-tinged, or finely red-mottled valves becoming papery, brown or stramineous, smooth or reticulate toward the angles, nearly always strigulose, occasionally glabrous; dehiscence at first apical, ultimately through the base and the ventral suture; ovules (4) 6-10 (12); seeds pale ocher, olivaceous, or purplish-brown, ± rugulose, (1.4) 1.7-2.6 mm. long.—Collections: 107 (xxvi); representative: J. Macoun (from Cypress Hills) in 1894 (NY); Hitchcock & Muhlick 11,888 (NY, RSA, WS); Christ 14,481 (NY); A. Nelson 1301 (NY, OB, RM, WIS), 4319, 7289 (NY, RM); C. L. Porter 4161 (NY, RM, SMU, TEX), 5402 (CAS, NY, RM, TEX); Ripley & Barneby 7916, 8715, 8770,10,523 (CAS, RSA).